D.V. Joshi

Toxicopathological evaluation in Wistar rats (Rattus norvegicus) following repeated oral exposure to acephate

The present study was carried out to evaluate the effects of exposure at different doses of acephate on hematology, blood biochemistry, oxidative stress and immune system of Wistar rats. The experiment was carried out on 40 Wistar rats, which were divided in four groups. Animals of the three treatment groups were given with different sublethal doses (1/40th, 1/20th, 1/10th of lethal dose 50 value) of acephate by oral gavage. The hematology, blood biochemistry, oxidative stress marker, humoral immune response and cell-mediated immunity were evaluated following acephate exposure. Significant alteration in hematological parameters was not observed following different doses of acephate; however, significant alteration in alkaline phosphatase, gamma glutamyl transferase, acetyl cholinesterase, lipid peroxidase and superoxide dismutase was observed in medium- and high-dose group animals. Nonsignificant decrease in antibody titer in animals exposed to high dose has been observed compared with animals of control group. However, significant alteration in cell-mediated immunity was not observed in animals treated with acephate at different doses.

Primary pulmonary adenocarcinoma in a Labrador retriever dog

A 10 years old Labrador retriever female had history of coughing along with occasionally hemoptysis, laboured breathing, restlessness and exercise intolerance. Radiography revealed extensive areas of pulmonary consolidation along with increased cardiac silhouette. The dog did not respond to treatment and succumbed. On necropsy, almost 90% of the caudal left lobe of lung was effaced and markedly expanded by neoplastic mass. On cutting, the tumorous lung revealed white to grey, firm, multi-lobulated mass with accumulation of mucus. Both the cardiac ventricles were dilated with more severity in right side. On microscopic examination, neoplastic cells of lung were arranged in papillary (predominate pattern), acinar or occasionally micropapillary pattern. High cuboidal to columnar neoplastic cells showed ample eosinophilic cytoplasm and round to oval nuclei. Alveoli were filled with inflammatory cells mixed with mucus. Neoplasm showed multifocal necrosis and hemorrhages. On the basis of gross and histopathology, the neoplasm was diagnosed as primary pulmonary adenocarcinoma.

A 28 days oral toxicity of Dronedarone in Wistar Rats (Rattus norvegicus)

The aim of the present experiment was to study clinical signs, haemato-biochemical alterations and pathomorphological changes induced by Dronedarone administration in rats. In present study, 48 Wistar rats (5–8 weeks old) were divided in to four different groups with equal numbers of male and female. Group I rats (Corn oil) severed as vehicle control. Group II, III and IV rats were administered Dronedarone @ 50, 100 and 200 mg/kg b.wt. respectively, orally daily for 28 days. The blood samples were collected on day 29 of the study from all the animals from retro-orbital plexus under carbon dioxide anaesthesia.

Pathology of experimentally induced acute toxicity of potassium dichromate in Wistar rats (Rattus norvegicus)

Potassium dichromate toxicity was induced in Wistar rats to study hematological, biochemical and histopathological alterations. Twelve Wistar rats weighing 200–250 g were divided into two equal groups, with one group (Group II) receiving potassium dichromate (K2Cr2O7) @ 25 mg/kg b. wt. orally by gavage as a single dose, and the other (Group I) serving as control was given normal diet. The rats were observed for 72 hours and sacrificed post treatment. Clinical signs such as dullness, depression and erection of hairs were observed in Group II rats. Haematology revealed significant (P<0.05) decrease in mean values of Hb, PCV and TEC and significant (P<0.05) increase in mean values of TLC in rats of treatment group. A significant (P<0.05) rise in mean values of plasma creatinine, urea nitrogen, ALT, AST and ALP was recorded in group II rats. Pathological changes comprised of congestion, hemorrhages, degeneration and necrosis in visceral organs. The lesions were prominent and severe in kidneys followed by liver.

Pathological studies on subacute toxicity of thioglycolic acid in Wistar rats (Rattus norvegicus)

In present study subacute oral toxicity of thioglycolic acid was evaluated in rats. Forty Wistar rats of either sex were divided into four groups. Group I rats received only distilled water as a control, while Group II, III and IV were given thioglycolic acid dissolved in distilled water dosedat the rate of 6, 12 and 24 mg/kg b.wt., respectively, by oral gavage daily for 28 days. Clinically, Group IV (high dose) rats showed lethargy and decreased activity after 21day of experiment. There was significant increase in haemoglobin level in Group II female rats and increase in TEC in Group II and III female rats as compared to control rats. Significantly decrease in ALP infemale rats of Group II, III and IV as compared to control rats. Significantly decrease in creatinine level in Group II, III and IV male rats. The male rats of Group III revealed a significant increase in calcium level. Triglyceride level was significantly (p<0.05) decreased and increased in female rats of Group II and III respectively as compared to control rats. There was significant decrease in absolute and relative adrenal weight in Group II, III and IV female rats as compared to control. Mild pathomorphological changes were seen in lung, liver and spleen. Microscopically, in Group IV rats, lungs showed perivascular mononuclear cell infiltration, minimal alveolar histiocytic infiltration, congestion and emphysema; liverevincedcongestion and perivascular leukocytic infiltration; kidney showed mineralization in tubules; and spleen revealed yellowish intracellular pigmentation. In conclusion, thioglycolic acid did not produce any significant pathology in Wistar rats at dose rates of 6, 12 and 24 mg/kg b.wt.

Potassium Dichromate induced genotoxicity and oxidative stress in Wistar rats (Rattus norvegicus)

The present study was designed to study Oxidative stress and genotoxicity induced by Potassium Dichromate in Wistar rats.50 colony bred Albino Wistar strain rats of either sex, divided uniformly into five different Groups. The rat of Group A received only Distilled water as control while, Group B, C and D were given Potassium Dichromate@ 0.625 mg/kg b.wt. (body weight), 1.25 mg/kg b.wt. and 2.5 mg/kg b.wt., respectively, orally by gavage for 28 days. Group E served as a positive control for genotoxicity given cyclophosphamide @ 20 mg/kg body weight intraperitonially prior to 24 hrs of sacrifice. The significant (P < 0.05) decrease in body weight was observed in rats of Group D from day 21st onwards. A significant dose dependent rise in Lipid peroxide level was observed in all chromium treated rats whereas, significant decrease in SOD values were observed in Group C and Group D rats. A dose dependent significant rise in chromium concentration in kidney, liver and lung were observed. There was dose dependent increase in the mean comet cell percentage in Group A, B, C and D. The present study indicates genotoxicity and oxidative stressin Wistar rats induced by Potassium Dichromate toxicity.

Pathomorphology of spontaneously occurring female genital tract lesions in buffaloes of North Gujarat

The objective of the present study was to determine the prevalence of female genital tract pathology in buffaloes of North Gujarat. A total of 179 buffalo genitalia collected from the slaughter house were screened for the presence of gross lesions. Out of 179, 57 (37.84%) genitalia were found grossly affected. The lesions observed were paraovarian cyst, 18 (10.06%) followed by bilateral inactive ovaries, 14 (7.82%), uterine serosal inclusion cyst, 6 (3.35%), aneurysms, 6 (3.35%), unilateral ovarian atrophy, 5 (2.79%), unilateral follicular cyst, 4 (2.23%) and one each of unilateral cystic corpus luteum, hematoma in paraovarian tissues, unilateral hydrosalpinx and mucometra.

A dose response study of monosodium iodoacetate induced femorotibial osteoarthritis in Wistar rats

In the present study, 18 female rats were randomly divided into 3 different groups. Each group consisted of 6 female rats. The right femorotibial joint of rats of the group I, II, III received 1, 3 and 5 mg monosodium iodoacetate (MIA), respectively at dose volume of 50 il/joint. The left femorotibial joint of rats of the group I, II, III received 50 il normal saline and served as control. Three rats from each group were euthanized on day 15 and 30 post injection. The clinical sign and histopathologic changes were clearly dose dependent. 5 mg MIA/joint produced marked joint swelling, lameness and lesions viz., degeneration and necrosis of chondrocytes, atrophy of articular cartilage, exposure of subchondral bone, fibrosis in marrow cavity and chondro-osteophyte formation on day 15 and 30. The rats of 3 mg MIA/joint showed similar clinical signs and lesions of milder severity. In 3 mg MIA/joint, chondro-osteophyte formation was seen on day 30. In 1 mg MIA/joint showed mild swelling, lameness and minimal necrosis of chondrocytes as compared to 3 and 5 mg groups. On basis of above findings it is concluded that 3 mg MIA/joint produced ideal osteoarthritisrat model.

Trichoepithelioma in goat: A case report

A surgically removed, formalin fixed tissue fromsoft, off white, ulcerated, glandular mass at junction of left teat and udder, of an about 5-year-old mixed breed goatwas submitted for histopathological evaluation. Microscopically, neoplastic mass was composed of islands and nests of neoplastic cells that form variable sized keratin filled cysts and supported by a moderate fibrovascular stroma. Neoplastic cells underwent incomplete trichogenesis. In the center of islands and nests of neoplastic cells showed matrical keratinization indicative of infundibular origin. On basis of histopathology, the tumor was diagnosed as benign trichoepithelioma.

Cervical leiomyosarcoma in a crossbred cow

A surgically removed, formalin fixed tissue from cervical tumorous mass from a7-year old Holstein-Friesiancowwas submitted for histopathological evaluation. Microscopically, unencapsulated neoplasm was composed of densely packed spindle shaped cells with cigar-shaped nucleiarranged in short interlacing bundles and admixed with collagenous stroma. Neoplastic cells showed diffuse strong reactivity for alphasmooth muscle actin. On basis of histopathology and immunohistochemistry, this neoplasm was diagnosed as leiomyosarcoma.